Swash plate compressor lubrication system

Abstract

A swash plate compressor for a motor vehicle air conditioning system has a lubrication channel in each of its valve plate faces which is open partially along its length by one of the suction reed valves to connect the compressor's crankcase directly with one of the pumping chambers in parallel with this valve's suction port during the intake stroke and is then closed by this suction valve along with the suction port during the discharge stroke.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
       1. A swash plate compressor that circulates refrigerant with entrained lubricant for compressor lubrication, said compressor comprising a pair of combined cylinder blocks having centrally located axially aligned shaft bores and radially and angularly located piston bores, said cylinder blocks defining a crankcase chamber therebetween, double-ended pistons mounted in the respective piston bores, a drive shaft, radial bearings mounting said drive shaft in the respective shaft bores, a swash plate fixed to said drive shaft and located in said chamber and operatively drivingly connected to said pistons, a pair of thrust bearings axially supporting said swash plate between said cylinder blocks, a pair of valve plates arranged on opposite ends of said combined cylinder blocks to close said cylinder bores and cooperate with the respective pistons to define pumping chambers, cylinder heads arranged with the respective valve plates to define suction cavities and discharge cavities at opposite ends of the combined cylinder blocks, each of said valve plates having a suction port and a discharge port for connecting each associated pumping chamber with the associated suction and discharge cavities, suction reed valves for opening the respective suction ports in response to differential pressure effected thereon by piston movement, discharge valves for opening the respective discharge ports in response to pressure rise in the associated pumping chamber, the improvement comprising: a lubrication channel in the piston side of each of the valve plates extending from the shaft bearing bore in the associated cylinder block behind one of the associated suction reed valves to an intermediate point between said shaft bearing bore and said one suction reed valve, said lubrication channel being sized and arranged so as to be closed along its length by said one suction reed valve when said one suction reed valve closes the associated suction port but then be opened by said one suction reed valve to the associated pumping chamber in parallel relationship with the associated suction port when said one suction reed valve opens whereby refrigerant with entrained lubricant is forced to flow from the crankcase chamber through at least the associated radial bearing and thence via the lubrication channel to the associated pumping chamber.   
     
     
       2. A swash plate compressor that circulates refrigerant with entrained lubricant for compressor lubrication, said compressor comprising a pair of combined cylinder blocks having centrally located axially aligned shaft bores and radially and angularly located piston bores, said cylinder blocks defining a crankcase chamber therebetween, double-ended pistons mounted in the respective piston bores, a drive shaft, radial bearings mounting said drive shaft in the respective shaft bores, a swash plate fixed to said drive shaft and located in said chamber and operatively drivingly connected to said pistons, a pair of thrust bearings axially supporting said swash plate between said cylinder blocks, a pair of valve plates arranged on opposite ends of said combined cylinder blocks to close said cylinder bores and cooperate with the respective pistons to define pumping chambers, cylinder heads arranged with the respective valve plates to define suction cavities and discharge cavities at opposite ends of the combined cylinder blocks, each of said valve plates having a suction port and a discharge port for connecting each associated pumping chamber with the associated suction and discharge cavities, suction reed valves for opening the respective suction ports in response to differential pressure effected thereon by piston movement, discharge valves for opening the respective discharge ports in response to pressure rise in the associated pumping chamber, the improvement comprising: a lubrication channel in the piston side of each of the valve plates extending from the shaft bearing bore in the associated cylinder block to an intermediate point between said shaft bearing bore and one of said suction ports in the respective valve plate, said lubrication channel being sized and arranged so as to be closed along its length by the suction reed valve associated with said one suction port when said one suction reed valve is closed but then be opened by said one suction reed valve to the associated pumping chamber in parallel relationship with said one suction port when said one suction reed valve opens said one suction port whereby refrigerant with entrained lubricant is forced to flow from the crankcase chamber through at least the associated radial bearing and thence via the lubrication channel to the associated pumping chamber.   
     
     
       3. A swash plate compressor that circulates refrigerant with entrained lubricant for compressor lubrication, said compressor comprising a pair of combined cylinder blocks having centrally located axially aligned shaft bores and radially and angularly located piston bores, said cylinder blocks defining a crankcase chamber therebetween, double-ended pistons mounted in the respective piston bores, a drive shaft, radial bearings mounting said drive shaft in the respective shaft bores, a swash plate fixed to said drive shaft and located in said chamber and operatively drivingly connected to said pistons, a pair of thrust bearings axially supporting said swash plate between said cylinder blocks, a pair of valve plates arranged on opposite ends of said combined cylinder blocks to close said cylinder bores and cooperate with the respective pistons to define pumping chambers, cylinder heads arranged with the respective valve plates to define suction cavities and discharge cavities at opposite ends of the combined cylinder blocks, each of said valve plates having a suction port and a discharge port for connecting each associated pumping chamber with the associated suction and discharge cavities, suction reed valves for opening the respective suction ports in response to differential pressure effected thereon by piston movement, discharge valves for opening the respective discharge ports in response to pressure rise in the associated pumping chamber, the improvement comprising: a lubrication channel in the piston side of each of the valve plates extending from the shaft bearing bore in the associated cylinder block to an intermediate point between said shaft bearing bore and one of said suction ports in the respective valve plate, said lubrication channel being sized and arranged so as to be closed along its length by the suction reed valve associated with said one suction port when said one suction reed valve is closed but then be opened by said one suction reed valve to the associated pumping chamber in parallel relationship with said one suction port when said one suction reed valve opens said one suction port whereby refrigerant with entrained lubricant is forced to flow from the crankcase chamber through at least the associated radial and thrust bearings and thence via the lubrication channel to the associated pumping chamber.